WO 2006/005668 (published in the US as US2007/186911, the contents of which are hereby incorporated by reference in their entirety) discloses a method for producing a ceramic filter element for an exhaust gas filter of internal combustion engines. In this connection, first a combustible, non-ceramic support web is impregnated with a ceramic slurry and the web is subsequently burned off in the desired geometric shape to such an extent that the support web is combusted and a rigid filter body remains. Such porous ceramic components can be used, for examples, as catalyst supports or for filtration applications, primarily in a high-temperature range.
For use as a filter element, an alternating closure of the passages is required, wherein the aforementioned method has the advantage that the closure can be provided already during manufacture of the paper elements so that no additional manufacturing step must be performed subsequently, as is the case for extruded honeycomb bodies, for example.
A variety of ceramic adhesives and potting compounds are commercially available, for example, from the companies Cotronics Corp. or Sauereisen. These compounds may be used for closing off the passages and are collectively referred to as potting compounds, ceramic adhesives or ceramic plugging, which provides filter elements that, after sintering, have a uniform pore distribution across their cross-section.
As can be understood, there remains a need in the art for a method for producing a ceramic filter element that avoids the aforementioned disadvantages of the prior art.